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    <title>Document</title>
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<script>

    function revrese(Arr) {
        for (var j = 0; j <= Arr.length-1; j++) {
            for (var i = 1; i < Arr.length - j; i++) {
                var temp = Arr[i-1]
                Arr[i-1] = Arr[i ]
                Arr[i ] = temp
            }
        }
        return Arr

    }
    // var arr = [5, 4, 3, 2, 1]
    alert(revrese([5, 4, 3, 2, 1]))
    
</script>

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